Seriously Good Vegan Gravy

Bahan-bahan (10 porsi)

• 3 tablespoons (42g) vegan butter (or extra virgin olive oil), (divided)
• 1 cup (120g) diced yellow onion ((or shallots, see Note 1))
• Kosher salt + freshly cracked black pepper
• 16 ounces (454g) cremini and/or shiitake mushrooms, (sliced (see Note 2))
• 5 cloves garlic, (chopped)
• 1 tablespoon fresh thyme leaves, (chopped (or 1 tsp dried thyme))
• 1 tablespoon finely chopped fresh rosemary leaves, ((or 1 tsp dried rosemary, crumbled with hands))
• 2 ¼ cups (540) low-sodium vegetable broth, (separated (see Note 3))
• ½ cup (120 mL) dry red wine ((such as Pinot Noir, Malbec, or Merlot) (see Note 4))
• 2 tablespoons (34g) soy sauce or tamari
• 2 tablespoons (10g) nutritional yeast
• 2 tablespoons (16g) cornstarch ((or arrowroot powder))
• 1 tablespoon (17g) white miso
• ¼ to ½ teaspoon balsamic vinegar ((or red wine vinegar))